6967-45-9Relevant articles and documents
Amine-Mediated Bond Cleavage in Oxidized Lignin Models
Li, Hongji,Liu, Meijiang,Liu, Huifang,Luo, Nengchao,Zhang, Chaofeng,Wang, Feng
, p. 4660 - 4665 (2020/07/04)
Introducing amines/ammonia into lignin cracking will allow novel bond cleavage pathways. Herein, a method of amines/ammonia-mediated bond cleavage in oxidized lignin β-O-4 models was studied using a copper catalyst at room temperature, demonstrating the effect of the amine source on the selectivity of products. For primary and secondary aliphatic amines, lignin ketone models underwent oxidative Cα?Cβ bond cleavage and Cα?N bond formation to generate aromatic amides. For ammonia, the competition between oxygen and ammonia determined the selectivity between Cα?N and Cβ?N bond formation, generating amides and α-keto amides, respectively. For tertiary amines, the lignin models underwent oxidative Cα?Cβ bond cleavage to benzoic acids. Control experiments indicated that amines act as nucleophiles attacking at the Cα or Cβ position of the oxidized β-O-4 linkage to be cleaved. This study represents a novel example that the breakage of oxidized lignin model can be regulated by amines with a copper catalyst.
A room temperature next amine control lignin model molecular breaking method
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Paragraph 0048; 0049; 0070; 0072, (2019/06/30)
The invention relates to a room temperature next amine control lignin model molecular breaking method. The method adopts the 1 - aryl - 2 - [...] as lignin β - O - 4 model molecule, in under the action of the copper salt and an amine, is oxidized and broken C - C/C - O key; wherein a primary and secondary aliphatic amine control into aromatic amide and a phenolic compound, inorganic ammonia control generating α - one amide and phenolic compound, tertiary amine control into aromatic acid and phenol compounds. The testing process are as follows: the 1 - aryl - 2 - [...], amine compound with a copper salt in dimethyl sulfoxide in mixed, put in the pressure container, the charge air or oxygen after the replacement is closed, at room temperature, stirring the reaction 8 - 12 is H, can occur model molecular C - C/C - O bond breaking, to obtain aromatic amide, α - one amide, aromatic acid and phenol compounds. The mild conditions, cheap catalyst and oxidizing agent, various controllable reaction product, the reaction process is simple and easy to operate.
Oxidative amidation of benzaldehydes and benzylamines with: N -substituted formamides over a Co/Al hydrotalcite-derived catalyst
Gupta, Shyam Sunder R.,Nakhate, Akhil V.,Rasal, Kalidas B.,Deshmukh, Gunjan P.,Mannepalli, Lakshmi Kantam
, p. 15268 - 15276 (2017/12/15)
The present work describes a highly efficient synthetic strategy for amides via oxidative coupling of benzaldehydes or benzylamines with N-substituted formamides using a heterogeneous Co/Al hydrotalcite-derived catalyst in the presence of TBHP. A series of Co/Al hydrotalcite-derived catalysts (Cat-2, Cat-3, and Cat-4 with the Co2+/Al3+ molar ratio in the synthesis mixture as 1/1, 2/1 and 3/1) have been prepared by a simple co-precipitation method and characterized using powder XRD, XPS, FEG-SEM, EDS, FT-IR, DTG-TGA and N2 physical adsorption techniques. Among the as-prepared catalysts, Cat-3 exhibited excellent catalytic activity towards the direct amidation of benzaldehydes as well as benzylamines bearing various substituents into the corresponding amides at 100 °C using TBHP as an oxidant. The mechanistic investigation of the amidation reaction revealed that the reaction follows a radical pathway. Furthermore, the catalyst is easily separable and recyclable without considerable loss in catalytic activity.
Copper-catalyzed amidation of benzoic acids using tetraalkylthiuram disulfides as amine sources
Zeng, Meng-Tian,Xu, Wan,Liu, Min,Liu, Xing,Chang, Cai-Zhu,Zhu, Hui,Dong, Zhi-Bing
supporting information, p. 1434 - 1440 (2017/08/16)
A facile method for the copper-catalyzed synthesis of N-substituted benzamides was explored. In the presence of CuBr and di-tert-butyl peroxide, various N-substituted benzamides were prepared through amidation of benzoic acid by using commercially available and cheap tetraalkylthiuram disulfides as amine sources. With this protocol, a series of 14 N-substituted benzamides were furnished in good to excellent yields. The broad substrate scope and good to excellent yield show its practical synthetic value in organic synthesis.
A 3,4-dimethoxy-N, N method for preparing-dimethyl-benzamide
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Paragraph 0024-0025, (2017/02/24)
The invention provides a new preparation method of 3,4-dimethoxy-N,N-dimethylbenzamide. 1,2-dimethoxybenzene, which is relative low in cost, is employed as a raw material in the method and is subjected to a reaction, catalyzed by anhydrous aluminium chloride, with N,N-dimethylaminoformyl chloride. An aimed product (II) is prepared through post-process. The preparation method is low in production cost, is simple and safe in operation and has an industrial production value.
Metal-Free Amidation of Acids with Formamides and T3P
Bannwart, Linda,Abele, Stefan,Tortoioli, Simone
, p. 2069 - 2078 (2016/07/06)
A new, simple and metal-free method for the direct formation of dialkylamides from carboxylic acids employing N,N-dialkylformamides as amine source is described. The one-pot reaction is promoted by propylphosphonic anhydride (T3P) in the presence of 0.5 equivalents of HCl.
Dimension-controlled assemblies of modified bipyrroles stabilized by electron-withdrawing moieties
Nakamura, Kazuto,Yasuda, Nobuhiro,Maeda, Hiromitsu
supporting information, p. 7157 - 7160 (2016/06/08)
Benzoyl-substituted bipyrroles possessing aliphatic chains were synthesized and formed a variety of dimension-controlled assembled structures as mesophases through various intermolecular interactions.
Direct amidation of alcohols with N-substituted formamides under transition-metal-free conditions
Xu, Kun,Hu, Yanbin,Zhang, Sheng,Zha, Zhenggen,Wang, Zhiyong
supporting information; experimental part, p. 9793 - 9797 (2012/09/05)
Go tandem! The first example of the direct amidation of alcohols with N-substituted formamides has been developed. A series of tertiary amides, including the challenging N,N-dimethyl-substituted amides, were obtained in moderate to good yields under transition-metal-free conditions (see scheme). TBHP=tert-butyl hydroperoxide. Copyright
Hansch analysis of veratric acid derivatives as antimicrobial agents
Narasimhan, Balasubramanian,Ohlan, Sucheta,Ohlan, Ruchita,Judge, Vikramjeet,Narang, Rakesh
experimental part, p. 689 - 700 (2009/09/08)
The synthesis, characterization and antimicrobial evaluation of a new series of veratric acid derivatives are presented. Preliminary in vitro antimicrobial activity of the title compounds was assessed against a panel of microorganisms including Gram-positive and Gram-negative bacteria and fungi. Some of the veratric acid derivatives exhibited significant in vitro antimicrobial activity. QSAR investigation applied to find a correlation between different physicochemical parameters of the veratric acid derivatives and their antimicrobial activity indicated the importance of topological parameters in describing the antimicrobial activity.
Total synthesis of (-)-tetrahydropalmatine via chiral formamidine carbanions: Unexpected behavior with certain ortho-substituted electrophiles
Matulenko, Mark A.,Meyers
, p. 573 - 580 (2007/10/03)
A method has been developed by alkylation of chiral lithioformamidines to construct protoberberine alkaloids with a C(9) and C(10) D-ring substitution pattern. This ring pattern was established using an ortho-substituted hydroxymethylbenzene electrophile protected as a silyl ether to ultimately provide (-)-tetrahydropalmatine in 88% ee. Additionally, we have discovered limitations with ortho-substituted electrophiles in the asymmetric formamidine alkylation. These electrophiles have the potential to disrupt the lithium formamidine chelate and cause the selectivity in the alkylation to be uncharacteristically low. The total synthesis of (±)-canadine and (-)-tetrahydropalmatine along with the limitations to the formamidine alkylation technology are delineated herein.
